Method of making a connection



1968 J. D. WETMORE 3,396,460

METHOD OF MAKING A CONNECTION Original Filed July 23, 1962 5Sheets-Sheet 1 I L m INVENTOR. Juana 00mg: WET/M025 Ea BY 6M 3, 1968 J.D. WETMORE 3,396,460

METHOD OF MAKING A CONNECTION Original Filed July 23, 1962 5Sheets-Sheet 2 P76; 5 my. Z

' INVENTOR p76, .44 1.0010 mm: W'r/I/QQE 1953 J. D. WETMORE 53,396,460

METHOD OF MAKING A CONNECTION Original Filed July 25, 1962 5Sheets-Sheet s United States Patent 3,396,460 METHOD OF MAKING ACONNECTION Judson Douglas Wetmore, San Diego, Calif., assignor toRaychem Corporation, Redwood City, Calif., a corporation of CaliforniaOriginal application July 23, 1962, Ser. No. 211,747, now Patent No.3,243,211, dated Mar. 29, 1966. Divided and this application Oct. 21,1965, Ser. No. 499,922

26 Claims. (Cl. 29-629) ABSTRACT OF THE DISCLOSURE This is a method ofmaking a composite article from two members. The first member comprisesa fusible member and a recoverable member with the recoverable memherbeing in abutting relation to the \fusible member. The first member ispositioned with the second member so that recovery of the recover-ablemember will urge the fusible member toward the second member and thispreform is then heated to cause the fusible member to become fluid andto cause the recoverable member to urge the fusible member toward thesecond member.

This application is a division of my copending application Ser. No.211,747, filed July 23, 1962, entitled Article and Process.

The present invention relates to articles which are capable of changingshape and which contain a fusible insert. The present invention includeswithin its scope articles in which the fusible insert operates torestrain the recoverable portion of the article against recovery andarticles in which the fusible insert does not restrain the recoverableportion of the article against recovery.

It has long been known that recoverable articles are useful Iforcovering other articles. For example, elastic rubber sleeves have oftenbeen used to cover cylindrical articles merely by choosing a sleevewhich, in its rel-axed condition, :has a diameter less than that of thearticle to be covered. The tendency of the sleeve to retract when it hasbeen expanded and placed over the article results in a covering for thearticle which, for some few purposes, is satisfactory. Heat recoverablearticles have also been used in a somewhat similar manner. An example ofsuch a heat recoverable member is found in Patent 2,027,962., issuedIan. 14, 1936, to Currie.

However, the recoverable articles known to the prior art have been foundto be completely unsatisfactory in the many instances when a strong andimpervious bond between the recoverable article and the article which isto be covered is desired. For example, it is common practice to laminatean insulating covering over electrical components such as conductors.The insulating material must, of course, be securely bonded to theconductor in order to protect the conductor from water or air or othermedia with which it may come into contact. Furthermore, it is alsohighly important that there be no air spaces between the covering andthe conductor. The occurrence of air spaces is particularly troublesomewhere the insulating material is applied to an element having anirregular surface, such as a plurality of wires which have been twistedtogether to form a cable or braided structure. Thus, as is well known tothose skilled in the art, there has been a long standing need forcoverings which are easy to apply, such as recoverable articles, and yetare capable of forming a secure, intimate, impervious bond with thearticle which is covered.

The present invention satisfies this long standing need in asurprisingly simple and economical manner.

One of the principal objects of the present invention is to provide arecoverable article capable of being laminated or otherwise united withanother article in such a 3,396,460 Patented Aug. 13, 1968 ice mannerthat a secure, intimate and impervious bond is formed and the process ofso doing.

Another object of the present invention is to provide a heat recoverablearticle capable of being laminated or otherwise united with anotherarticle in such a manner that a secure, intimate and impervious bond isformed and the process of so doing.

A further object of the present invention is to provide a heatrecoverable article having elastic memory which is capable of beinglaminated or otherwise united with another article in such a manner thata secure, intimate and impervious bond is formed and the process of sodoing.

It is still another object of the present invention to provide anarticle and process for forming a laminated or otherwise unitedinsulating covering which is securely, mt-imately and imperviouslybonded to electrical elements.

It is a further object .of the present invention to provide arecoverable article having a fusible insert and processes for using thisarticle.

Other objects and advantages of the present invention will becomeapparent from the following detailed description, when read inconjunction with the drawings, of preferred embodiments of the presentinvention.

Briefly, the present invention comprises, in part, a recoverable articlewhich is provided with a fusible insert. The recoverable articles of thepresent invention may comprise elastic materials which have beenstretched and are held in the stretched condition, heat recoverablearticles, such as articles made from materials having the property ofplastic memory, or the like. The fusible inserts of the presentinvention may comprise any suitable fusible material, e.g.,thermoplastics such as polyolefines. Furthermore, the word insert, asused in the description of the present invention, contemplates anymember which is positioned such that it will be interposed between therecoverable material and an article with which the recoverable materialis to be laminated or otherwise united. For example, in those instanceswhere a tubular article is to be provided with an inner liningcomprising the recoverable material, the insert comprises a fusibleouter layer provided on the outer surface of the recoverable material.The process of the present invention comprises forming the recoverablematerial such that it has a dimension different from that of the articleto which it is to be laminated or otherwise united and such that it hasthe property of being capable of changing its dimensions. Therecoverable material is then provided with fusible material which ispositioned such that it will be interposed between the recoverablematerial :and the article to which it is to be laminated or otherwiseunited. The fusible insert is preferably in abutting relation to therecoverable member. The article of the present invention is thenpositioned with relation to the article to which it is to be laminatedor otherwise united in such relation that change in the dimensions ofthe recoverable mate rial will cause it to urge the fusible membertoward the article to which it is to be attached and cause it to becomebonded thereto. The article of the present invention is then subjectedto sufiicient heat to cause the fusible material to become fluid. In aprefer-red embodiment of the present invention, where recoverablearticles having the property of elastic memory are employed, theapplication of heat also causes the recoverable material to exercisethis property. Furthermore, the preferred embodiment of this inventioncomprises a recoverable member which is capable of changing itsdimensions in response to the application of heat at a given temperatureand a fusible memberwhich will become fluid at the same temperature.

In the drawings:

7 FIGURE 1 illustrates an embodiment of the article of the presentinvention in which the article has a tubular shape.

FIGURE 2 illustrates another embodiment of the present invention inwhich the recoverable member is a split cylinder.

FIGURE 3 illustrates still another embodiment of the present inventionwherein the recoverable member is mounted on a coil spring.

FIGURE 4 illustrates another embodiment of the present invention whereinthe recoverable member is closed at one end.

FIGURE 5 illustrates another embodiment of the present invention whereinthe recoverable member is closed at one end and contains a ball ofsolder.

FIGURE 6 illustrates another embodiment of the present invention whereinthe recoverable member is closed :at one end and contains a ball ofsolder and electric conductors.

FIGURES 7 and 8 illustrate embodiments of the present invention whichare similar to the embodiments illustrated in FIGURES 5 and 6,respectively, except that the recoverable member is open at both ends.

FIGURE 9 illustrates an embodiment of the present invention wherein therecoverable member comprises a spirally wrapped article.

FIGURE 10 illustrates an embodiment of the present invention wherein theconductors encapsulated by the article of the present invention havebeen crimped.

FIGURE 11 illustrates an embodiment of the present invention wherein oneconductor is spirally wound about another before the conductors arespliced.

FIGURE 12 illustrates an embodiment of the present invention wherein thefusible member comprises a longitudinally perforated cylinder.

FIGURES 13A-D illustrate :a preferred embodiment of the presentinvention wherein the fusible member functions as a dam for solder.

Referring now to the drawings, FIGURE 1 illustrates a preferredembodiment of the present invention wherein the recoverable member 1 andfusible insert 2 are tubular in shape. In a preferred embodiment of thepresent invention, the recoverable material is a heat recoverablematerial having the property of elastic memory, :such as the materialsdisclosed in US. Patent No. 2,027,962. When this type of recoverablematerial is used, the fusible insert may comprise virtually any materialcapable of being rendered flowable by the application of heat. Forexample, conventional thermoplastic materials such as polyolefines(polyethylene, polypropylene, etc.), polyamides (e.g., nylon), polyesters(e.g., polyethylene terephthalate, cellulose acetate), and other similarmaterials. It is, however, to be understood that the present inventionis not limited to the use of conventional thermoplastics as the fusibleinsert. Rather, thermosetting materials such as epoxy resins,polyurethanes, phenol-aldehyde condensation products, etc., may also beused. Still further, it is possible to use, in combination with therecoverable material, certain materials which would not operate inprecisely the same manner as fusible materials, such as insulating orconductive greases or heat catalyzed adhesives and the like.

In the preferred embodiment wherein the recoverable member is a heatrecoverable member having elastic memory properties, the fusible insert2 may be combined with the recoverable material 1 in any suitablemanner. For example, the .fusible material may be applied to therecoverable material as a coating or the fusible insert may be formedinto a predetermined size such that it will be held by the recoverablemember simply by frictional forces, i.e., by a force fit. It will beobvious to those skilled in the art that, when practicing the presentinvention in accordance with this preferred embodiment, the recoverablemember must, in general, be deformed in such a manner that it possesseselastic memory properties before the fusible insert is added. There areseveral well-known methods according to which recoverable materials maybe deformed such that they possess the property of elastic memory. Onesuch method is clearly disclosed in U.S. Patent No. 2,027,962, which isincorporated herein by reference. As disclosed in this patent, suchmaterials are independently dimensionally heat unstable, i.e., capableof changing dimension to assume a heat stable condition upon theapplication of heat alone. Thus, unlike thatembodiment of the presentinvention illustrated in FIGURE 2 wherein fusible member 4 holds spring3 under tension, thereby rendering spring 3 heat recoverable when thefusible member 4 is heated to an extent such that it is no longercapableof resisting the compressive force exerted by spring 3, theapplication of heat will cause the independently dimensionally heatunstable material 1 illustrated in FIGURE 1 to change dimensionregardless of whether the fusible member 2 is present. Any such methodmay be used in the practice of the present invention. Ordinarily, thefusible insert is added to the recoverable material after therecoverable material has been caused to assume dimensions in which ithas the property of elastic memory. However, the fusible insert of thepresent invention may be added to the recoverable member in particulateor powder form. When the article of the present invention is heated, thefusible particulate material flows to form an impervious coating. Whenthe [fusible material is added to the recoverable material inparticulate form, the addition may be performed before or after therecoverable material is deformed such that it possesses the property ofelastic memory. Thus, the use of particulate fusible material has theadvantage that the article of the present invention may be assembledwithout causing the recoverable material to assume any given dimensions.The assembled article may then be deformed by the user to the preciseextent required by a given purpose [for which the article is to be used.

In another embodiment of the present invention, the recoverable material1 may comprise an elastic material such as natural or synthetic rubber.In this embodiment, the fusible insert must possess sufiicientstructural strength that it is able to withstand the compressive forcesexerted by the recoverable material after it has been distended.According to this embodiment, the fusible insert is first formed to asize different from that of the article to which the article of thepresent invention is to be laminated or otherwise united. For example,as illustrated in FIGURE 1, elastic material 1, which has a diametersmaller than that of insert 2 when it is in the relaxed state, isstretched over insert 2. The combined recoverable material 1 and insert2 may then be placed over an article to be encapsulated, such as anelectric conduit or the like, which is of a diameter substantially thesame as, or somewhat larger than, the original relaxed diameter of therecoverable material 1. The encapsulation is accomplished by theapplication of sufficient heat to fuse or break down the crystallinestructure of insert 2, thereby causing insert 2 to lose its rigidity andpermitting the recoverable material 1 to contract elastically toapproach its original dimension. The result is a highly effectivebonding of recoverable material 1 to the encapsulated article. Thismethod may be used for true encapsulation in the sense of fusing theinsert 2 to the member to be encapsulated, or may function simply toproduce a heat shrinkable elastic tube wherein the rigid insert is usedonly for the purpose of temporarily maintaining the recoverable materialin its expanded condition.

In the embodiment of the present invention illustrated in FIGURE 2, therecoverable material is a split-cylinder type spring 3 which is heldunder tension by rigid fusible insert 4. Spring 3 is illustrated asbeing made from metal, but it is to be understood that spring 3 maycomprise other suitable materials such as plastic or hard rubber.Furthermore, it is also to be understood that the relation of members 3and 4 may be reversed such that rigid fusible member 4 surrounds spring3 and holds it under tension. The function of this embodiment of thepresent invention is essentially the same as that previously describedwith respect to the use of a stretched elastic material as therecoverable material.

FIGURE 3 illustrates an embodiment of the present invention whereinrecoverable material 5, which has a circular horizontal cross-sectionand is provided with fusible material 6 which is suitably bonded, e.'g.,by adhesive, thereto, holds coil spring 7 in compression. In thisembodiment, recoverable material 5 comprises a material possessing theproperty of elastic memory. When the assembly illustrated in FIGURE 3 isheated, the recoverable material 5 releases the compressive forces whichit exerts on spring 7. Spring 7 then functions to urge fusible portions6 into contact with the article with which the assembly is to be united.

FIGURES 4-6 illustrate embodiments of the present invention in which therecoverable material 8 has a closed end. This closed end may be formedby sealing, by appropriate means, one end of a tubular member, or may beformed simply by molding a thimble shaped article. The articlesillustrated in FIGURES 4-6 are particularly useful for terminatingelectrical conduits.

The embodiment illustrated in FIGURE 4 is essentially the same as thatillustrated in FIGURE 1, with the exception that one end of therecoverable member 8, which surrounds fusible member 9, is closed.

In the embodiment illustrated in FIGURE '5, a ball of solder and flux ispositioned within fusible member 9. Thus, when the assembly illustratedin FIGURE 5 is heated, not only is fusible member 9 caused to fuse andrecoverable member 8 caused to contract to a smaller diameter, but theball of solder and flux 10 is also caused to fuse. The solder thussupplements member 9 as an encapsulating material.

In FIGURE 6, recoverable member 8 is illustrated as it would appear withfusible member 9, ball of solder and flux 10 and wires 11 insertedtherein.

The embodiment illustrated in FIGURE 7 is essentially the same as thatillustrated in FIGURE 5 with the exception that recoverable member 12 isopen at both ends.

The embodiment illustrated in FIGURE 8 is similar to that illustrated inFIGURE 7, with the addition that a rigid sleeve 13, preferablycomprising metal, is inserted within fusible member 9. It is preferredthat rigid member 13 have an axial dimension less than that ofrecoverable member 12 and fusible member 9. Thus, when heat is appliedto this assembly, the recoverable member contracts down around the sidesof rigid member 13. It is to be understood that solder 10 may be omittedfrom this embodiment.

Since the articles of the present invention are particularly suitablefor splicing and terminating the ends of electrical conduits, theprocedure for so using the articles of the present invention will bedescribed in some detail.

The embodiment illustrated in FIGURE 6 may be used for making awaterproof soldered splice on plastic insulated wire ends. The splicecan be accomplished without stripping the wire ends, twisting the wireends, flexing the wire ends, crimping the wire ends together or othercommonly used methods. The fusible member 9 of the article of thepresent invention should be a material which is capable of fusing orbonding to the plastic insulation on the wire. As shown in FIGURE 6, therecoverable article is provided with solder and, if desired, a fluxingmaterial. The unstripped wire ends 11 are pressed against the top of thesolder. Heat is then applied to the assembly. High frequency inductionheating has been found suitable in those cases wheer solder is used.When the heat is applied, the recoverable member 8 contracts toencapsulate or surround the fusible material 9 which is melted by theheat. The heat also causes the insulation on the wires to migrate awayfrom the ends thereof, thereby exposing the wires. The heat furthercauses the solder to fuse around the exposed wires. Upon cooling, asplice which is securely bonded and impervious is obtained.

The embodiment illustrated in FIGURE 8 functions in substantially thesame manner as that illustrated in FIG- URE 6, with the exception thatthe wires, or other objects, to be spliced may be pushed toward eachother along the axis of the tube in order to form a butt type orparallel type junction.

As illustrated in FIGURES 1 and 4, the solder may be omitted where it isnot necessary, e.g., where soldered wires are being covered.Furthermore, as illustrated in FIGURE 7, the sleeve 13 may be omitted ifthe structural strength which it imparts is not required.

In those instances where the recoverable member of the article of thepresent invention is to be tubular in shape, the tube may be extruded,molded or fabricated from a flat sheet of material simply by rolling itinto a tube and suitably sealing the seam. Where greater cornpressiveforce is desired than that which may be obtained with a single layer ofrecoverable material, the fiat sheet may be rolled into a tube in such amanner that a series of spirally Wound layers are formed as illustratedin FIG- URE 9. The compressive forces exerted by the spirally woundlayers 14 on fusible member 15 are substantially greater than thoseexerted by a single layer of recoverable material.

In those instances where the rticle of the present invention is used tosplice electric conductors and in which it is desired to omit thesolder, e.g., the embodimerits illustrated in FIGURES l and 4, it hasbeen found desirable, as illustrated in FIGURE 10, to apply crimpingforce to the spliced conductors 16 and 17 at the point where the exposedconductors are in contact with each other. The crimping assures that aneffective connection is made between the conductors. The crimping may,of course, be performed either before or after the article of thepresent invention comprising fusible member 18 and recoverable member 19is used to splice the connectors.

As illustrated in FIGURE 11, particularly where a splice is to be madewithout the use of solder, the insulation may be stripped from one ofthe conductors 20 for sufficient length to expose a portion of theconductor which is long enough to be spirally wrapped around the exposedportion of the other conductor 21. After the spiral winding isperformed, the article of the present invention, comprising fusiblemember 22 and recoverable member 23, may then be used to effect thesplice in any of the manners described herein.

Where a plurality of conductors are to be spliced independently, orwhere a plurality of articles are to be independently encapsulated, theembodiment of the present invention illustrated in FIGURE 12 may beused. In this embodiment, fusible member 24 is-provided with a pluralityof perforations 25. When heat is applied to the article, recoverablemember 26 will contract and fusible member 24 will become fiowable.Thus, individual articles which are to be spliced or encapsulated may bepositioned in perforations 25 and heat then applied to assembly. Thisembodiment of the present invention has the distinct advantage that thepossibility of voids or air spaces occurring between the articlespositioned in perforations 25 is substantially eliminated.

It will be readily apparent to those skilled in the art that the devicesof the present invention have numerous and varied uses. For example,they may be used to join two or more pieces of metal and/or plastictogether, for joining two or more cylindrical or square pieces of tubingtogether, for joining two or more pieces of tubing or rod orcombinations thereof together, for the application of casters to chairlegs, and for sealing bottle caps or for sealing covers on containers.Furthermore, these articles may be used for lamination in general, forconnection of any two similarly shaped objects, for forming a moistureproof covering on one or more objects, for making a chemical resistantcovering for one or more objects, as well as for splicing,encapsulating, etc., of electrical elements.

As illustrated in FIGURES l3A-D, the fusible insert of the presentinvention may perform multiple functions. According to this embodimentof the invention, recoverable member 27 is first molded or otherwiseformed into the shape illustrated in 13A such that it is provided withrecessed portion 28. The article is then deformed as illustrated inFIGURE 13B so as to impart elastic memory properties thereto accordingto any of the well-known processes for so doing such as those which havepreviously been described. Article 27 is then provided with fusibleinsert 29 and solder 30 as illustrated in FIGURE 130. Electricalconductors 31 having insulating covering 32 thereon are then insertedinto the interior of article 27 as illustrated in FIGURE 13D. Heat isthen applied to this assembly which causes recoverable article 27 toreturn to its original configuration (illustrated in FIG- URE 13A), andwhich also causes fusible insert 29 and solder 30 to become fluid. Theheat also causes insulation 32 to migrate away from the ends ofconductors 31, which migration is illustrated after partial completionin FIGURE 13]). Since the ends of conductors 31 are located in recessedarea 28, the contraction of recoverable material 27 will cause fusibleinsert 29 to come into contact with insulation 32 without causingrecoverable member 27 to come into contact with conductors 31.Furthermore, since the density of solder 30 is greater than that ofinsulation 32, the solder will tend to force the insulation away fromthe ends of conductors 31. The fusible material 29, after theapplication of heat, forms a dam around conductors 31 which prevents theescape of solder 30 and assures an effective splice of conductors 31.

It will be obvious to those skilled in the art that many variations ofthe fundamental concepts previously described are possible withoutdeparting from the scope of the present invention. For example, thearticles of the present invention may have any desired configuration.The configuration of the articles of the present invention will, in mostcases, be determined by the shape of the articles to which they are tobe laminated or otherwise united. Furthermore, although the foregoingdescription has described in most detail those embodiments in which therecoverable member is caused to assume a final dimension less than thatwhich is posseses in the recoverable state, it is to be understood thatthe present invention is equally applicable to recoverable members whichexpand rather than contract. For example, by providing a tubularrecoverable member with a fusible member which surrounds the recoverablemember, an article which is particularly suitable for the lining oftubular members such as pipes is produced. The expandable recoverablearticle of the present invention is, for example, positioned within apipe which it is desired to line, and heat is applied to the article,The article of the present invention is thus caused to expand indiameter and the fusible material is caused to become fiowable. Theresultant product is a pipe which has been provided with a securelybonded lining of the recoverable material.

The recoverable member of the present invention may comprise anirradiated or chemically cross-linked polymeric material. Polyolefinesare a particularly suitable type of polymeric material for this type ofrecoverable material. The polymeric material is first extruded orotherwise molded into a desirable shape. The polymeric material is thencross-linked or given the properties of cross-linked material byexposure to ultra-violet radiation or high energy radiation, e.g., ahigh energy electron beam, or by chemical means, e.g., peroxides whenpolyolefines are used. The cross-linked polymeric material is thenheated and deformed, and then locked in that condition by quenching orother suitable cooling means or, in the alternative, the same processcan be accomplished at IQQLI fimperature by using greater force todeform the polymeric material, The deformed material will retain itsshape almost indefinitely until exposed to a temperature above itscrystalline melting temperature, e.g., approximately 250 F. in the caseof polyethylene.

Other materials which have been found to be particularly satisfactoryfor use in the present invention are heat recoverable elastomericmaterials and *polytetrafluoroethylene. In general, any materialpossessing the property of elastic memory (sometimes referred to asplastic memory), as well as other recoverable materials, such as elasticor rubbery materials, may be used in the practice of the presentinvention.

It will be apparent to those skilled in the art that the recoverablearticle of the present invention may be formed into a variety of shapeswhich will result in various flow patterns of the fusible material or,if it used, the solder. Furthermore, the recovery of the recoverablemember may be controlled by the insertion of rigid members in thearticles'of the present invention in order to cause the recoverablematerial to recover in a desired manner. For example, a coil spring maybe embedded in either the recoverable member or the fusible member orattached merely by the tension exerted by the spring itself such thatthe recoverable material will cause the spring to become elongated,compressed or a combination of both. Still further, the recovery of therecoverable member may be controlled by differential heating such thatone portion of the member will undergo a greater change in dimensionthan another portion. The heating described in the present applicationmay be a positive application of heat, e.g., radiation heating,induction heat ing, electric resistance heating, heat generated by anexothermic reaction, etc., or may constitute the exposure ofrefrigerated materials to atmospheric, or lower, temperatures. Forexample, a crystalline elastomeric material could be distended, held inthe distended state and subjected to refrigeration to freeze it in itsdistended state. This article could then be provided with a fusibleinsert which would become fluid at, say, room temperature. Such anarticle would then operate according to the present invention merely byexposure to room temperature.

Still further, the fusible insert of the present invention may be suchthat it is capable of becoming fluid at the same temperature as thatrequired to cause the recoverable member to change dimension, or it maybe capable of becoming fluid at either a higher or lower temperaturethan that required to cause the recoverable member to change dimension.Where the fusible material comprises a thermosetting material, the heatmay also cause this material to harden as well as causing it to becomefluid.

The induction heating used in the practice of the present invention maybe any type of high frequency heating.

The articles of the present invention have many uses other than thosepreviously described. For example, the fusible material may function tocause a bond to be formed, to fill voids, to release a spring or othersimilar element, as a dam to prevent the flow of another fluid, etc. Theforce exerted by the recoverable member may function to move anotherobject, to cause a secure bonding, to release a diaphragm which closesor opens a conduit, etc.

Having fully described the present invention, it is to be understoodthat it is not to be limited to the specific details set forth, but isof the full scope of the appended claims.

I claim:

1. The method of making a composite article comprising a first memberand a second member, said method comprising: selecting as the firstmember, a preform, said preform comprising a recoverable member and afusible member, said recoverable member being in abutting relation tosaid fusible member, said preform having dimensions different from atleast aportion of the second memher which is to form at least a part ofthe remainder of said composite article; positioning said preform andsaid second member such that the recovery of said recoverable memberwill urge said fusible member toward said second member; and heatingsaid preform to an extent suflicient to cause said fusible member tobecome fluid and to cause said recoverable member to urge said fusiblemember toward said second member.

2. The process of claim 1 wherein said recoverable member comprises amaterial having the property of elastic memory.

3. The process of claim 2 wherein said recoverable material comprises acrosslinked polyolefin.

4. The process of claim 3 wherein the recoverable material comprises apolyolefin which has been chemically crosslinked.

5. The process of claim 3 wherein said recoverable member comprises apolyolefin which has been crosslinked 'by irradiation.

6. The process of claim 2 wherein said recoverable member comprises anelastomeric material.

7. The process of claim 2 wherein said recoverable member comprisespolytetrafluoroethylene.

8. The process of claim 1 wherein said fusible member comprises athermoplastic.

9. The process of claim 1 where said fusible member comprises athermosetting material.

10. The process of claim 1 wherein said fusible member is contiguouswith said recoverable member.

11. The process of claim 1 wherein said fusible member is in particulateform.

12. The process of claim 1 wherein said preform is provided with a ballof solder, said solder being in abutting relation with said fusiblemember.

13. The process of claim 1 wherein said preform is provided with a rigidmember, said rigid member being in abutting relation with said fusiblemember.

14. The process of claim 12 wherein said preform is provided with arigid member, said rigid member being in abutting relation with saidfusible member and with said solder.

15. The process of claim 1 wherein said recoverable member comprises anelastic material.

16. The process of claim 1 wherein said fusible member comprises aperforated cylinder.

17. The process of claim 1 wherein said second member comprises at leastone electrical conductor.

18. The process of claim 17 wherein said electrical conductors are fullyinsulated and said heating is sufficient to cause said insulation tomigrate away from the ends of said conductors.

19. The process of claim 17 wherein one of said conductors is spirallywrapped around another of said conductors.

20. The process of claim 17 including the step of crimping saidconductors.

21. The process comprising applying heat to a recoverable article, saidarticle comprising a recoverable member and a fusible member, saidrecoverable member and said fusible member being in abutting relation,said heat being applied differentially to said article, said heat beingsufficient to cause said fusible member to become fluid.

22. The method of making a composite article comprising a first memberand a second member, said method comprising the steps of selecting apreform as the first member, said preform comprising a tubular articlehaving at lea-st one open end and having a wall comprising a materialwhich has been dimensionally changed from an original heat stable formto a dimensionally heat unstable material which is capable of moving inthe direction of its original form upon the application of heat aloneand a fusible member in abutting relation with said wall and positionedwithin the direction of dimensional change of said wall, said preformhaving dimensions different from at least a portion of the second memberwhich is to form at least a part of the remainder of said compositearticle, positioning said preform and said second member in telescopingrelationship with said second member being in the direction ofdimensional change of said wall, the dimensional stability of said wallbeing such that different portions thereof will undergo dimensionalchange to a different extent upon the application of heat so as tosubstantially prevent the passage of said fusible material beyond saidone end, and heating said preform to an extent sufficient to cause saidfusible member to become fluid and to cause said wall to undergodimensional change as aforesaid.

23. The method of making a composite article comprising a first memberand a second member, said method comprising the steps of selecting asthe first member a preform, said preform comprising a tubular articlehaving at least one open end, the wall thereof comprising a materialwhich has been dimensionally changed from an originally heat stable formto an independently dimensionally heat unstable material capable ofmoving in the direction of its original form upon the application ofheat alone and a fusible member in abutting relation to said wall andpositioned within the direction of dimensional change of said wall,positioning said preform and said second member in telescopingrelationship, said one end comprising means for substantially preventingthe passage of said fusible material beyond said one end upon theappliaction of heat sufficient to cause said dimensionally unstablematerial to change dimension, and heating said preform to an extentsufiicient to cause said fusible member to become fluid and to causesaid wall to urge said fusible member towards said second member asaforesaid.

24. The process of claim 23 wherein said fusible member is solder.

25. The process of claim 23 wherein said means for substantiallypreventing flow of said fusible material comprise a second fusiblemember in abutting relation to said wall and positioned within thedimensional change of said wall, the first fusible member having aviscosity which is low relative to the viscosity of said second fusiblemember at a temperature at which said dimensionally heat unstablematerial undergoes dimensional change.

26. The process of claim 1 wherein said heating is performeddifferentially.

References Cited UNITED STATES PATENTS 2,739,829 3/1956 Pedlow et a1.2,790,285 4/1957 Pike et a1 5342 X 2,898,714 8/1959 Keith 53--303,017,302 1/ 1962 Hultkrans. 3,022,543 2/ 1962 Baird et al. 3,037,5296/1962 Hancik 138-109 3,037,868 6/1962 Rosser. 3,040,385 6/ 1962 Folta29-613 X 3,187,088 6/1965 Warner 174--84 X 3,226,807 1/ 1966 Orr.3,276,929 10/ 1966 Ferch.

FOREIGN PATENTS 1,054,527 4/ 1959 Germany.

JOHN F. CAMPBELL, Primary Examiner.

J. L. CLINE, Assistant Examiner.

